Robbie Brady's 85th-minute goal for the Republic of Ireland ensures Norn Iron will face a battle of Britain against the Welsh at the Parc des Princes, rather than a last-16 tie with hosts France in Lyon, a fixture now on the Republic's own schedule.

Brady's winner also sends Northern Ireland into the half of the draw that does not feature world champions Germany, reigning European champions Spain, Italy, France or England.

O'Neill's team met Wales as recently as March, though they recorded a 1-1 draw against a team missing Gareth Bale and Aaron Ramsey, and the prospect of a reunion on a Saturday night in the French capital is mouthwatering.

"It is going to be a fantastic game," O'Neill said.

"We will be heading back to the Parc des Princes which, as we know from Tuesday night, is a brilliant stadium. We will benefit from the familiarity of having been there already, of having done the journey and of having played on the pitch.

"The results put is in what is arguably the more favourable side of the draw, so we are pleased about that.

"We are in no doubt that it is going to be a tough game against Wales but we will go into the match believing that we can win and that we can progress."

Speaking on Wednesday afternoon before knowing whether he would be preparing his team for the Welsh or the French, O'Neill noted that a return journey to Paris, where they were beaten by Germany on Tuesday, would give them shorter preparation time.

"Wales have done exceptionally well," he said.

"Having won the group, they will be in a good place confidence-wise. Gareth Bale's had a very good tournament. It will be a very difficult game.

"They also have a day's recovery ahead of us, we travel again to Paris which is another thing we have to deal with."